A Lakeview couple who escaped from their burning apartment on Sunday left their front door open so that their pets could escape the flames, contributing to the spread of the deadly fire, fire officials said today.

"They told the fire investigators that they propped the door open so animals could get out," said Larry Langford, a spokesman for the Chicago Fire Department. "I can tell you that the door being left open contributed to the spread of the fire."

Langford said investigators learned that the couple had propped the door open with a rug from interviews with them, not from evidence that was found at the scene. The couple were unavailable for comment on Monday.

The blaze swept through the 12th floor at 3130 North Lake Shore Drive at about 2 a.m., according to Fire Department Chief Joe Roccasalva. Shantel McCoy, who had moved to Chicago last March, died when the elevator opened on the 12th floor in the midst of the fire. She was hit with 1,500-degree temperatures and killed, Roccasalva said.

On Monday, Langford said the fire may have been started by candles or electrical equipment, but he said investigators were still examining the debris to find a cause.

Since the 21-story building was constructed before 1975, it did not have a sprinkler system installed. The building was also not required by law to have automatic fire alarms throughout the building or any sensors to shut the elevators down during a blaze, Langford said.

McCoy entered the elevator on the ground floor at the same time that the fire department received the emergency call from the building, Langford said. Firefighters entered the building about five minutes after she arrived to the 12th floor and was fatally injured.

The building is one of hundreds of residential high-rises exempt from current sprinkler requirements that were supposed to make the buildings safer, Langford said.

On Monday, residents of the building said they were outraged to learn that there was no way they could have been alerted that there were flames consuming an apartment. And they were concerned that the elevator system was not wired with sensors to detect a blaze.

"It doesn’t cost that much money to install those sensor systems," said Eric Miller, who lives on the 12th floor and knew McCoy. "How many people have to die? I’m so angry about this. It's unbelievable."

Steven Giardino said he and Miller stayed in their apartment on Sunday night, but the fumes and smells are forcing them today to seek shelter at a hotel.

A woman who had moved to Chicago last March died early today after she unwittingly went up an elevator as a fire was blasting through the 12th floor of the high-rise apartment where she lived, officials said.

The Chicago Cubs on Tuesday sought City Hall permission to expand construction hours at Wrigley Field, with bleacher work falling well behind schedule on the team's $375 million ballpark renovation project.

On Wednesday night, TBS will air a special episode of "Conan" filmed entirely in Cuba, making it the first American late-night show to broadcast from the island nation since the embargo went into effect in 1962. Host Conan O'Brien will follow in the footsteps of Jack Paar,...

"Star Wars Rebels" continues to offer up gifts for the fans. On Monday's first-season finale, it reintroduced the beloved character Ahsoka Tano from "The Clone Wars" animated series. Now it's recruiting a former vampire slayer.